Decades of research in evolutionary biology and cognitive science have led many esteemed scientists to the conclusion that, according to the precepts of universal Darwinism, humans are merely the hosts for two replicators (genes and memes) that have no interest in us except as conduits for replication. Stanovich shows here how concepts of rational thinking from cognitive science interact with the logic of evolution to create opportunities for humans to structure their behavior to serve their own ends. These evaluative activities of the brain, he argues, fulfill the need that we have to ascribe significance to human life.